- The fungus attacks the plants during all stages of growth. Pre emergence damping off and post emergence seedling mortality also can occur.
- In the older plants, the characteristic wilt symptoms appear when the leaves lose their turgor and hang down during the hot periods.
- The wilting progresses gradually and cause characteristic tip burn symptoms on the foliage of the affected plants.
- During wet conditions, dead stems are covered with pinkish white masses of the pathogen.
The fungus is seed borne and is a soil inhabitant. In the presence of host roots, the chlamydospores of the causal fungus germinate and cause infection of the fibrous roots. Wilt development is favoured by temperature around 270C.
Observe plants from 10 pits in the plot. Look for wilt symptoms and note the number of plants infected.